Slashdot Mirror
"Vegetative State" Patients Can Communicate
Kittenman writes "The BBC is carrying a story about researchers in the UK and Belgium who can detect the thinking processes within a patient previously thought to be in a vegetative state. The researchers ask the patient verbally to think in certain ways to indicate a 'yes', in other ways to indicate a 'no' — and have successfully communicated with 4 out of 23 patients previously thought to be in a coma."
From TFA:
"Patients in a vegetative state are awake, not in a coma, but have no awareness because of severe brain damage. "
It's official. Most of you are morons.
This is not really surprising if you are aware what a real coma is. There is a lot of states between fully consciousness and complete unconsciousness. In movies, and in soaps you switch between those states in a surprise wake-up. In reality this is much more complex.
Anyway, better diagnosis is needed to prevent accidents like Brain scan finds man was not in a coma--23 years later and other possible improvements in brain damage treatment.
The problem of improper controls and false positives is really serious with these fMRI studies. It can be summed up in three words, really: Thinking dead salmon.
I don't think they addressed the "no answer" vs. "B", however, they did assess the patients' ability to answer a series of factual questions about the patient's life prior to whatever put them where they were - I think that pretty much shows that there is something non-spurious being measured here and it's not just the dead salmon fMRI effect as another reply suggested - the probability of random readings matching up with the correct answers to a series of such questions seems very minute.
And 4 out of 23 is not a success rate - it's a misdiagnosis rate! Nobody in their right mind is claiming that *all* patients in persistent vegetative states have meaningful cognition occurring (except the EXTREMELY inaccurate and misleading Slashdot article title). Rather, some patients who failed the standard tests to assess consciousness levels are perhaps more conscious than was previously detectable.
Yes responses were indicated by one type of mental imagery, no responses by another, so yes and no were both distinguishable from "no answer."
The scanning was done in a fashion that is typical of fMRI studies in that an active condition was alternated with a rest condition. In fMRI it's essentially impossible to get a meaningful activation without contrasting two different conditions, in this case Answer with Relax, so the "activation" that is measured is a comparison between the answer and relax conditions. If a subject just had continuous spurious activation in the target brain region: 1) it wouldn't have been identified in the localizer task (described briefly below) and 2) it wouldn't show up as a differential activation between the Answer and Relax periods.
The subjects first underwent a "localizer" task to determine what particular region of the motor cortex to use for their responses. They alternated periods of mental imagery (imagining playing tennis, and imagining navigating through a familiar city) with relax. This identified the regions that would later be used to indicate Yes or No responses (one type of imagery for yes, the other for no).
Not to ruin the funny but I was horribly bored so here goes ...
ZAP: Philip J. Fry, you stand accused of travelling to the forbidden planet Omega 3. A crime punishable by 12 concurrent death sentences. Do you understand the charges? ...
KIF; One beep for yes, two beeps for no.
FRY: *BEEP*
ZAP: Yes. So noted. You pleed guilty?
FRY: *BEEP* *BEEP*
ZAP: Double Yes. Guilty. I will now carry out the sentence
It's the first minute and a half or so from the episode "Where no fan has gone before" if someone is wondering.
Of the 54 patients examined in the study most had suffered either from traumatic brain injury or anoxic brain injury. Anoxic brain injury for the most part means your heart had stopped for a prolonged period of time (although other things such as severe prolonged hypoglycemia or carbon monoxide can do the same thing). Anoxic brain injury is a diffuse process and its course is highly predictable. Depending on the severity of the initial event with anoxia patients will either improve after a relatively short period of time or they never will. Of all of the 'miracle' re-awaking cases that have occurred (extremely rare cases of people waking up to a severely disabled state) none of them have been by someone who has suffered anoxia.
Traumatic brain injury has a less predictable course as some of the parts of the brain are destroyed while other parts can be relatively undamaged. Of the five patients in the study who were found with some brain activity all of them were traumatic brain injury cases.
Schiavo suffered anoxic brain injury due to cardiac arrest. These patients never need fancy brains scan as their external findings accurately reflect what has happened to their entire brain. The current New England Journal of Medicine article actually serves to support that anoxia patients have no cognition.
Yes, living wills, and informing your loved ones to remove you from life support in such cases are very important. But as the Schivo case proved, it doesn't really matter when religious politics become involved. Your living will is only as valid as the willingness of your relatives to honor it.
Schiavo did NOT have a living will, which was the cause of the interminable legal wrangling. Had she clearly designated someone to exercise medical power of attorney, there would have been no controversy. Instead, the Florida default rules it fell to her husband who claimed that she had orally represented to him that she did not want to be kept alive in such a case. Her parents claimed that she would not have, given her religious faith. "Religious politics" had nothing to do with it. Quoting Wikipedia (my emphasis)
Given the lack of a living will, a trial was held during the week of January 24, 2000, to determine what Schiavo's wishes would have been regarding life-prolonging procedures. Testimony from eighteen witnesses regarding her medical condition and her end-of-life wishes was heard. Michael claimed that Schiavo would not want to be kept on a machine where her chance for recovery was minuscule, her parents claimed that Schiavo was a devout Roman Catholic who would not wish to violate the Church's teachings on euthanasia by refusing nutrition and hydration.
Honestly, the case really boils down to that -- who do we believe is best qualified to take an essentially random guess about what a person would want. Ideologues on both sides tried to make it into more than that but it just wasn't. If she was genuinely religious and would have wanted to be kept alive, we should have kept her alive. If she would have wanted to die, we should have let her die. The resolution of this essentially factual question (in the absence of any reliable evidence) neatly solves the entire affair.
To summarize, if we can learn anything from the whole shitfest, please leave notarized documentation of your desires. Not even for yourself (although that should be motivation enough) but so your loved ones can feel confident in your wishes instead of being forced to guess. That is not a burden I would wish on the people that care about me, nor do I think it's fair to give them that responsibility. The document does not have to be complicated or expensive -- it can be as simple as designating a person to chose for you.